More than a quarter of local authorities in England have failed to prosecute a single landlord over the last five years – and a further half are prosecuting fewer than two a year.
In total, 2,006 criminal landlords have been convicted in the past five years, with the average fine being just £1,500.
The data comes from responses to Freedom of Information requests by the Residential Landlords Association.
Lawyer David Smith, policy director of the RLA, said: “Tenants and good landlords are being let down.
“Councils have plenty of powers to enforce standards in private rented housing and tackle criminal landlords. It is sad that at best the record on enforcement is patchy and at worst non-existent.”
The RLA is campaigning for councils to drop licensing schemes and use their existing powers instead to bring criminal landlords to justice.
It points out that these powers will be significantly beefed up under the new Housing and Planning Bill, which will introduce a register of rogue landlords and agents, and for the first time, give a legal mechanism for criminal agents to be banned from the industry.
The RLA also says that the Bill makes landlord licensing schemes redundant because councils will be able to collect information about tenure and landlords on Council Tax forms.
Smith said: “The Housing Bill makes clear that landlord licensing schemes are not needed and serve only as a money raising exercise by councils.
“Local authorities now have serious questions to answer. Why are they charging good landlords when they can collect the information they need to drive out criminal landlords using council tax registration forms for free.”
According to Citizens Advice, rogue landlords are milking the State benefits system.
Chief executive Gillian Guy said: “Dodgy landlords make as much as £5.6 billion a year from renting out homes that don’t meet legal standards and £1.3 billion of this bill is picked up by the state in the form of housing benefit.
“Tenants are having to pay soaring rents despite severe damp, rat infestations and even the risk of explosions.”
Shelter has claimed that almost half a million private rental homes have bad living conditions, including damp, mould, electrical hazards and infestations.
Shelter chief executive Campbell Robb said: “The Government must to do more to protect renters from the rogue landlords who let out these shoddy properties, so that every renter can feel safe in their own home.”